1. Field of the Invention
The present invention relates to lasers. More specifically, the present invention relates to systems and methods for improving the performance of high power lasers.
2. Description of the Related Art
Spatial filtering has been used in low-power systems to improve the beam quality of a laser beam. This approach simply discards the portion of the beam that lies outside the desired far field central lobe, thereby reducing the efficiency of the laser. Unfortunately, this approach is impractical for high power lasers due to the excess power required and heating of the blocking aperture.
Other approaches have involved an adjustment of various design parameters to improve fidelity. The design parameters for phase conjugate lasers have included a number of incoming beam parameters such as beam divergence, beam diameter, polarization state, pulse shape and format, wavelength, aberration shape or order, coherence and so on. Other design parameters that might be adjusted include parameters of the conjugator such as the length of the nonlinear medium; geometries of the beam interactions inside the nonlinear medium such as focus, beam intersection, length of the beam overlap region, angle between beams, choice of nonlinear medium and etc.
Unfortunately, this approach forces undesirable compromises in design. Further, this approach has been heretofore unsuccessful in the attainment of the fidelity required for current and future applications.
Hence, there is a need in the art for a system or method for improving phase conjugation fidelity in high power phase conjugate lasers and other electro-magnetic systems.